Projectors, which are image display apparatuses that enlarge and project various images on a screen, have been widely used (for example, see Japanese Unexamined Patent Application Publication No. 2009-199854). Known specific systems of the projectors include projecting an image by causing light from a light source to pass through a transmissive image-projecting device and projecting an image by reflecting light from a light source off a reflective image-projecting device.